Although a portable communication terminal like a smartphone can carry out communication in different wireless communication schemes such as Bluetooth (registered trademark: the mention of which will be omitted below) and a wireless LAN (Local Area Network), it usually uses a common antenna (referred to as a “single antenna system” from now on) in the wireless communication schemes to meet a space-saving demand.
The single antenna system achieves communication through a single antenna while avoiding interference between the wireless communications by carrying out the communications in both the wireless communication schemes in time division.
On the other hand, as for onboard equipment like a car navigation system, since its space-saving demand is not so rigid as a portable communication terminal like a smartphone, it sometimes assigns different antennas to the Bluetooth and wireless LAN (referred to as a “dual antenna system” from now on). Generally, since the dual antenna system can ease restriction on the time-division operation as compared with the single antenna system, it can improve the throughput of the wireless LAN.
For example, Patent Document 1 discloses a technique that carries out priority control or switches between a simultaneous operation and a time-division operation in accordance with a packet state of the wireless LAN and Bluetooth in a wireless communication device that carries out wireless communications using the wireless LAN and Bluetooth.
In addition, Patent Document 2 discloses, in a wireless communication device carrying out wireless communications based on a wireless LAN and Bluetooth, a technique that switches in accordance with a transmission range between a parallel operation (referred to as a “simultaneous operation” from now on) which carries out the respective wireless communications using two antennas, and a time-division operation which uses a single antenna in common.